Hydrostatic holding devices have been used for a number of years to hold work parts which are to be machined or ground. U.S. Pat. No. 2,744,756 (May 8, 1956) shows an expansible elongate sleeve to underlie a work part. Another U.S. Pat. No. 3,030,120 (Apr. 17, 1962) shows the use of an expandable sleeve to expand an adapter to hold various work parts. The hydrostatically operated sleeve has also been used to contract inwardly to hold sleeve type work parts as illustrated in U.S. Pat. No. 3,677,559 issued Jul. 18, 1972.